EXTENSIVE POLYMORPHISM OF ABO BLOOD-GROUP GENE - 3 MAJOR LINEAGES OF THE ALLELES FOR THE COMMON ABO PHENOTYPES

Polymorphism of the ABO blood group gene was investigated in 262 healt hy Japanese donors by a polymerase chain reactions-single-strand confo rmation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A (1) (provisionally called ABOA101, *A102, *A103 and *A104 according t o the guidelines for human gene nomenclature), 3 for B (ABOB101, *B10 2 and B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O 203). Nucleotide sequences of the amplified fragments with different S SCP patterns were determined by direct sequencing. Phylogenetic networ k analysis revealed that these alleles could be classified into three major lineages, A/*O1, *B and *O2. In Japanese, *A102 and *B101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, O101 (43%) and O201 (53%), were observed. These results may be useful for the estab lishment of ABO genotyping, and these newly described ABO alleles woul d be advantageous indicators for population studies.